DNA Isolation Lab

DNA Isolation from wheat germ - work in pairs! DNA the Molecule of Life chromosomes cell DNA gene T T T A A 4 T G AT A G G 4 1. Mix 50 ml of hot water and 1.5 g wheat germ in a small cup or beaker. 2. Stir with a wooden skewer. 3. Add 2 pipette squirts of detergent (the detergent dissolves the lipid cell membranes). 4. Add 1.5 of meat tenderizer (the tenderizer contains papin enzyme that breaks down protein. This removes the histone proteins from the DNA). 5. Stir for a couple of minutes. 6. Let the mixture settle for a couple of minutes. 7. Pour the liquid part of the solution into a 50 ml polypropylene tube-leave most of the wheat germ in the cup. The DNA should be in the solution. Fill the tube halfway. 8. Pour ice cold ethanol SLOWLY down the inside edge of the tube you filled in step 7. Fill the tube almost to the top (the ethanol helps the DNA come out of solution). 9. DNA strands will begin to precipitate and form! Yes, they look like snot. Twist the DNA onto the wooden skewer. This is called DNA spooling. DO NOT STIR OR SHAKE! Human Cheek Cell Station 1. To view cheek cells, gently scrape the inside lining of your cheek with a toothpick. DO NOT GOUGE THE INSIDE OF YOUR CHEEK! 2. Gently roll & tap the toothpick onto the center of a glass slide with a single drop of water. Some of the cheek cells will fall onto the slide. 3. Cover with a cover slip using proper procedure. 4. Observe the cheek cells under scanning, low and high power of your microscope. 5. Add a drop of methylene blue stain or iodine. This is done by placing a drop on the side of the cover slip and placing a paper towel on the opposite edge of the cover slip. This should draw the stain through and color the cells. 6. Observe the cheek cells under low and high power of your microscope (at the minimum you should observe the cell membrane, nucleus, and cytoplasm). Human cheek cells Stomata This is the structure of a leaf The 'bottom'layer of a leaf is called the lower epidermal layer. In land plants, stomata are located in this layer. Some floating aquatic plants, like water lilies, have the stomata located on the upper side of the leaf. Submerged aquatic plants do not have stomata. epidermis vein palisade mesophyll spongy mesophyll moist air space Moma gward cells In botany, a stomate (plural stomata) is a tiny opening or pore, found mostly on the undersurface of a plant leaf, and used for gas exchange. Air containing carbon dioxide and oxygen enters the plant through these openings where it gets used in photosynthesis and respiration. Waste oxygen produced by photosynthesis exits through these same openings. Also, water vapor is released into the atmosphere through these pores in a process called transpiration. CO, in O Star of Africa's Savanna Ecosystems May Be the Lowly Termite: Regularly Spaced Termite Mounds Are Key to Maintaining Ecological Function ScienceDaily (May 26, 2010) The majestic animals most closely associated with the African savanna- fierce lions, massive elephants, towering giraffes may be relatively minor players when it comes to shaping the ecosystem. The real king of the savanna appears to be the termite, say ecologists who've found that these humble creatures contribute mightily to grassland productivity in central Kenya via a network of uniformly distributed colonies. Termite mounds greatly enhance plant and animal activity at the local level, while their even distribution over a larger area maximizes ecosystem-wide productivity. The finding, published in the journal PLoS Biology, affirms a counterintuitive approach to population ecology: Often it's the small things that matter most. "It's not always the charismatic predators animals like lions and leopards that exert the greatest control on populations," says Robert M. Pringle, a research fellow at Harvard University. "As E.O. Wilson likes to point out, in many respects it's the little things that run the world. In the case of the savanna, it appears these termites have tremendous influence and are central to the functioning of this ecosystem." Prior research on the Kenya dwarf gecko initially drew Pringle's attention to the peculiar role of grassy termite mounds, which in this part of Kenya are some 10 meters in diameter and spaced. some 60 to 100 meters apart. Each mound teems with millions of termites, who build the mounds over the course of centuries. After observing unexpectedly high numbers of lizards in the vicinity of mounds, Pringle and his colleagues began to quantify ecological productivity relative to mound density. They found that each mound supported dense aggregations of flora and fauna: Plants grew more rapidly the closer they were to mounds, and animal populations and reproductive rates fell off appreciably with greater distance. What was observed on the ground was even clearer in satellite imagery. Each mound -- relatively inconspicuous on the Kenyan grassland stood at the center of a burst of floral productivity. More importantly, these bursts were highly organized in relation to one another, evenly dispersed as if squares on a checkerboard. The result, says Pringle, is an optimized network of plant and animal output closely tied to the ordered distribution of termite mounds.